Evaporator



Nov. 6,1923, 1,473,373 v M. JKKERMER EVAPQRATOR Filed Jan. 16 1919 2 Sheets-Sheet 1 Irufenjii? JAZ'I'WI' F3 MM '1 Nov. 6, 1923. 1,473,373

M. J. KERMER EVAPORATOR Filed Jan. 15 1919 2 Sheets-Sheet 2 Inlfefitf)? a Marizhl 1121722227 9 'additively to, and

Patented Nov. 6, 1923.

entree s'raras MARTIN J. KERMER, OF EVANSTON, ILLINOIS.

EVAPORATOR.

Application filed January 16, 1919. Serial No. 271,542.

To all whom it may concern:

Be it known that I, MARTIN J. KERMER, a citizen of the United States, residin at Evanston, in the county of Cook, and tate of Illinois, have invented certain new and useful Improvements in Evaporators, of which the following is a specification.

My invention relates to evaporators and particularly, in most of its features, to evaporating systems in which the liquor is subjected to treatment in a concentrator after it has passed through a multiple-effect system which I will term the primary system. It is known practice to treat the liquor through a primary system,=-say a triple-effect or quadruple-effect installation-and then to pass it to a concentrator which acts to further the degree of concentration; but in all such systems with which I am familiar the concentrator acts merely in a sense independently of, the primary system and it in no way affects the operation of the primary system. In prior systems that include a concentrator there is usually a material loss of solid matter which is entrained with, and passes out with, the vaporfrom the.concentr'ator, and to minimize this loss special catch-all equipment for the concentrator is requisite. Further, in. some of such systems there is considerable steam-waste incident to the concentrator operation, for the vapor passes out of the concentrator at relatively high temperature.

My invention, in one-sense, contemplates a novel inter-relation between evaporator units, such as a concentrator unit and a firsteifect unitwhich are severally heated by steamand the equipment of the system for control of vapor pressure in one of said units by regulation of its steam supply. In another aspect my invention combines a concentrator with a primary evaporation system, making a unit of such primary system serve as a catch-all for the concentrator. so that entrainment-loss from the concentrator is impossible, all of the vapor from the concentrator being delivered into the primary system. In another sense my invention provides for operating a concentrator withmultiple-effect steam-economy, causing its vapor to work in. the primary evaporator system. And in a further sense my invention aifords steam regulation of a first-effect unit (i. e., the unit receiving the the vapor space of one of the line steam) of a primary evaporating system accordantly with the pressure-variationtendencies that are manifested in one of the primary units and'which may have wide range when varying quantities of vapor are delivered thereto from a concentrator.

In the embodiments of my invention which I have shown and will particularly describe, the liquor (for example a potassium and sodium brine) is subjected to treatment in a multiple-effect primary system one unit of which (called the first effect) is supplied with steam, and the vapor-outlet pipe of the concentrator, (which of course is also supplied with steam) delivers the Vapor and entrained solids from the concentrator into primary units precedent to the lastor ultimate efiect. In this way, such solids-losses as ordinarily occur where a concentrator is used are avoided, and the necessity for supplying a catch-all in connection with the concentrator is obviated, and further the vapor from the concentrator is utilized in the steam-space of a subsequent efi'ect, influenc ing therefore, all effects subsequent to that into which it is introduced, so that the concentrator is itself worked with multipleefi'ect steam economy. Of course, in the ordinary operation of a concentrator the quantity of vapor delivered therefrom may vary widely, and so I provide, in the primary system, means for such compensatory regulation of steam supply to the first-effect as may maintain the intended working pressures of the several units at the points requisite for greatest economy. Preferably I accomplish this regulation of the steam supply to the appropriate unit by automatic means, and further, preferably, I effect the automatic steamt control in a manner that is consistent with the maintenance of very active circulation in the 'first-efi'ect unit, So that its'efiicacy will not be seriously decreased 'due to the regulating action.

From the following description-it will be' apparent that the features offmy invention set forth and claimed are susceptibleo'f-em bodiment in varied formsand arrange rients of apparatus, and so it will be understood that, while for clarity of illustration I have diagrammatically represented evaporators, and a concentrator, of known commercial design, I do not intend'to limitm'y invention cific installation illustrated to the selection 01*: end ede'ptetion end arrangement oi, the illusttetively shown.

in the drawn: ig, l s a side elevation wlth ports in sec iagre nmeticeily show" ing; e t uple-efi emoooying my invview of the s s; i 3 is E- .1

one s outline ruple-eilect system tion.

In Figs, 1 enl 2, numerals ii, ill, end ii represent the three evaporator units of e triple-effect primary system, wherein the liquor, introduced at inlet 19 follows the course indicetel hy sol arrows. introduced into the second-e i. e., the unit whose steam-space receives vapor from the first effect), it owe thence through pipe ii to the third-effect, and is iorced by pump 12 through pipe 13 to the lirsteilect, whence it may he delivered through pipe 14 by pump 15 to the concentrator C, Pipe it, beyond x w m J. centietoi syst A. KG sketch oi quad the pump 15 preiemh-ly has n valved branch 16 to the concentrator, another valved branch 17 delivering to the storage tank 18 from which the liquor may he introduced into the concentretor by valved pipe 19. @f course the concentrated product may be drawn oil from the concentrator, its at velve delivery pipe 20.

Steers is supplied to the heater 2' of the first-effect by the steam pipe 21, the vapor from this unit passing, as indicated by dotted arrows, throu h pipe 22' and catch-all 23' to the heater m of the second-effect unit ll; vapor from the seco-nd-eilect passing similerly through pipe 2 end catch-ell 23" to heater of the third-eli'ect, the vepor pipe 22 of which is connected through catch-ell 23 with the condenser 2t end vacuum pump 25. Return pipes 28 from. each catch-ell to the liquonspece of its corresponding unit-shell are provided, and suit ehle provision is made as by equalizing: pipe 27, mnning from the thir eiie ct vapor space to pump 12, to equalize the pressure of the third efieet vapor-space end the pump chamber. The pump, oi course, is power driven by any means, not shown, and works under suhe-tinospheric pressure in the speit will he understood ti in the diagramnietic ilhistretion it have omitted the customery incidents of eveporetor systerns, such as gages, gas-reliefs, condensation dneins, waste pipes, flushing connections, etc

it will he understood that the sequence ot the several effects is determined as to firstj? seco id, etc, by the steam-space pressure, but that with relation to iiquor-progress the order may he varied, thet shown being especielly desirehle where precipitation of solids is apt to take place it the finel steges oi eve oi ion econ). et Mira 7 J, t J.

es is 1/, "or example, Wit sodium, potassium, e d other selt solutions.

spece of one of the rnult oleunits precedent to the ultimate encct in this instance into the first-eii'ecP-so that the two elements C and that receive steern their heaters e e interreleted for d iiveiy of the m the former to the vapor-space of the letter, so that the vapor from the concentrator G may be utilized th the vepo-r o unit i in the heating of the liquor in unit ll, fhus, inevitably, the entrained nieteriel passing out of the concentrator is caught in the primeiy system, the con centretor imposes no entrainment-losses on the openation of the system, further the concentretor is arranged to operate with multiple-effect economy.

()1 course the quantity of vapor pessing from the concentretor to eveporeting unit I is subject to wide variation, decrees ing as the liquor becomes more and more dense, and since this variant quantity ct vepor is introduced directly into the vapor space of one of the primary units, it will be apparent that working vapor-pressures throughout the several primary effects would be disturbed, and efiiciency would be opt to be reduced, if compensatory action in the primary system were not provided for. Therefore I provide regulating means, preferably eutomatic, for varying the action of the firstcffect unit to maintain the desired pressure condition in. the vapor-spaces of the several units notwithstanding the tendency to pressure-variation imposed by reason of the stated connection of the concentretor with said first efiect unit, In general it accomplish this by automatically regulating the quantity of steam admitted to the heater oi the first-effect unit, and in this niechenism 35, the premiere chamber of 3 which hes pipe-connection 36 to the vaporspece oi the unit I.

The novel operation of the installation as shown will he as follows: Disregurding, for

the moment, the concentrator end the special opening of the provisions made with respect thereto, the action of the triple-effect system would be as usual in an installation (not novel per Sc) where the liquor is introduced into the second-effect and passes successively through the third and first-effects; that is to say, the several primary units would maintain their appropriate relative pressures in their vapor-spaces as long as properly served with steam and raw liquor. Manifestly the installation might be so worked without callin the concentrator into action. In the speci 0 installation shown, the raw liquor is first treated in the second effect, where the vapor space may be under, say, approximately a 13-inch vacuum and the steam basket works under, say approximately 8 pounds pressure. Thence the liquor passes to the third effect where the vapor-space vacuum may be, say 25 inches and and the steam basket is working under approximately a 15-inch vacuum. Thence the liquor is pumped, by pump 12, to the first effect where the pressure in the vapor space may be, say, 8 pounds and the steam basket may be served with steam at, say about pounds pressure. Of course the foregoing is illustrative only, and not limitational, as the conditions may be widely varied, according to the temperature-requirement of the concentrator, the final vacuum attained, and the size and design of the heatin" surfaces.

Vhen, however, the concentrator begins working on a charge of relatively dense liquor, vaporization therein is initially rapid, so that a large volume of vapor passes over through pipe 30. Pressure in the vapor space of unit I tends, therefore, greatly to increase, but the automatic operation of valve cutting off or minimizing the steam supply to the section 32 of heater 2' so decreases the evaporation local to the unit I that the vapor premure acting through pipe 22 to serve the second-effect heater will be only approximately normal. As concentration goes on in concentrator unit C and the vapor coming over to unit I decreases in volume, the consequent pressure-reduction-tendency in unit I results in automatic valved connection 35 to admit an adequate amount of steam to the outer section 32 of heater 5 of the first effect to maintain the pre-determined pressure. of course, hand regulation of the steam may be substituted for or used additionally to the automatic regulation contemplated for the first-effect, although I regard the stated automaticity uable as a part of my invention.

While the construction of heater for reception of the variable steam supply may be changed, I regard that shownnamely, a cylindrical, flat-headed, liquor-tube drum, of sectional construction wherein one secof action as desirable and valtion is constantly under the full steam-pros sure-as especially desirable, in that its physical construction is simple and more especially in that by providing asection thus heated to the full degree I can insure in the first-effect unit that forceful circulation and ebullition of the liquor which is usually so desirable. Furthermore, as shown in Fig. 3, this provision for full-heating in one section may be furthered if desired, and the external section 32 divided into plural sub-sections, as 32 and 32", into which, successively, steam will be admitted as the automatic valved mechanism 35' responds to continuing tendency to pressure decrease, the valve mechanism-such as the tandem valves 35 and 35", diagrammatically illustratedbeing of such character that they will be successively opened, and will close in reverse succession, soserving steam properly to the two pipes 84' and 34".

It will be observed that not only is all of the solid matter saved which otherwise would escape through the concentrator-pipe 30, and this without the provision of a separate catch-all, but further the steam requirement for the satisfactory operation of the system is minimized, the concentrator, as well as the first-effect unit, working in connection with the second and third effects, to attain triple-effect economy.

It will be understood that the principles of my invention are not restricted to a tripleefi'ect system. The important consideration is, of course, to be taken into account that a concentrator usually develops a vapor pressure above atmospheric, while a primary evaporator-system usually shows a sub-atmospheric pressure or vacuum in its pcnultimate efi'ect. Hence the simplest practice, from the standpoint of evaporatordesign, is to deliver the concentrator-vapor into a unit that should normally carry a pressure approximating that developed in the concentrator. In a quadruple-effect system, for instance, as shown in Fig. 4, the connection 30 may be made to deliver the concentrator-vapor into the second-effect rather than the first, and the regulation of steam-supply to the first-effect may be either from the second-effect-shell, by connection 36'. or from the first-effect shell as shown in Fig. 1. Other changes may be made in arrangement, the suggested modification sufiicing to indicate that the application of the invention claimed is not restricted to a single organization.

What I claim is:

1. In an evaporator system, the combination of a multiple-effect primary evaporating system wherein the vapor space of the firstefl'ect unit is connected with the steam space of the second-effect unit and so on to the ultimate effect, which has a vapor outlet, and wherein the liquor spaces of the several with the vapor space of the ultimate effect,

a concentrator having its liquor space receptively connected With the liquor space of that unit which is last in liquor-flow sequence; means-to supply steam at above atmospheric pressure to the steam space of the concentrator; ineans to supply steam shove at ospheric pressure to the steam space of the first-etlect unit; and a vapor delivering connection from the vapor space of the concentrator to the vapor of a unit precedent to the ultimate e whereby said concentrator acts ltiple-etlect steam-economy,

in evaporator system, a n1 evaporating system or than tvvo units, each said unit having v or space connected to the heating space next subsequent etlect, and the u eirlect having'a vapor-delivery out et, centrator; means for steam supply to heating space of. the first unit, steam supply to the heating space ct concentrator; liquor-flow he the liquor spaces of the evaporator units, a liquor flow connection "from that unit which is last in liquor-lion sequence to the liquor space of the concentrator; and means for delivering the concentrator vapor from the vapor space of said concentrator into the vapor space of the ante-penultimate unit of the multiple-efiect system.

3. In an evaporator system, the combine-- tion of more than two multiple-efiect pri= mary units, each having a vapor space con= nected to-the heating space of the next subsequent unit, and the vapor space of the ultimate unit having a vapor outlet; means of steam supply to the heating @ace of the first unit; a-concentrator having its vapor space permanently connected to deliver into the vaporv space of a suitable one of said units, precedent to the ultimate efiect unit, means to supply steam to the heating space oi the concentrator, and means or regulating the steam supply to said first unit.

i lln an evaporator system, the combination of multiple-efiect primary-units, each having a heating-space and a vapor space, the latter connected to the heating-space oilthe next subsequent unit, means of steam supply to the heating-space of the first unit, a concentrator having a vapor space connected to deliver to the vapor space of one oi said units, and automatic means for reg lating the steam supply to said first unit to main tain the pressures throughout the units Suhstantially uniform. under variations in pressure imposed by the concentrator,

5. The combination of a plurality of el ments, each having a steam space, a liquorand-vapor space, and an outlet pipe from the latter, one said element having its outlet pipe c c d vvi-c the vapo space lenient, means for roducirg p o the space of the said eleinc automatically control d to reducing steam into the space of other element to inaintau suhstantic uniform pressure in its vapor space notwithstanding variation in the vaponsupp y flowing thereto from the one said elemei.

o. The (301 incision oi an evaporator unit having a liquor-and-vapor space and a vapor outlet, a steam space and connection for supplying thereto, a second unit having a liquor-and-vap-or space and a vapor outlet, its said liquor-and-vapor space being connected to the outlet of the first unit, the second said unit having a divided space with respective passages "for ditlerent portions or the liquor, constantly-open connections supplying steam to one of the divisions of said space, and means for vary= ing t ,e supply of steam to the other of the divisions of said space to maintain substantially constant the pressure in the vapor space, I

7, The combination of an evaporator unit having a liquor-andvapor space and a vapor outlet, a steam space, and connection for sup-plying steam thereto, a second unit having a liquor-and-vapor space and a vapor outlet, its said liquor-and-vapor space connected to the outlet of the first unit, the second said unit having a divided steam space with respective passages for difierent portions of the liquor, constantly-open connections tor supplying steam to one of the divisions of said space, and automatic means for varying the supply of steam to the other of the divisions 0 said space to maintain substantially constant the pressure in the vapor space,

8. lhe combination of an evaporator unit having a liquor-and-vapor space and a vapor outlet, a steam space and connections for supplying steam thereto, a second unit hav ing a liquor-and-vapor space and a vapor outlet from said liquor-and-vapor space, its said liquor-and-vapor space hein con nected to the outlet of the first unit, the second said unit having a cylindrical liquortuhe heater partitioned to divide its interior into two distinct steam spaces, normally open connections for supplying steam to one of said steam sections, steam supply means for the other section, and automatic means for varying the supply of steam to said other section to maintain suhstantially constant the pressure in the vapor space of said unit,

9., in a multiple-sheet evaporator system, a plurality of elements vhaving steam-spaces and means for separately supplying steam thereto ahove atmospheric pressure, unit a heater connected to receive the means for a till lltl

vapor from said plural elements, and means for regulating the steam supply to one of said elements for maintaining substantially constant the vapor pressure supplied to the heater of said unit.

10; In a multiple-efi'ect evaporator s stem, a first-eifect unit havin a heater an having variable steam supp y connections thereto; other evaporator unitshaving heaters each receptively connected to the vapor space .and a of the preceding efiect; a concentrator having a heater and steam supply connections thereto, and having its vapor space connected to the vapor space of one of the said evaporator units precedent to the ultimate effect;

ressure responsive re ulator controlled rom the last mentione evaporator unit and controlling the variable steam connections for the first-effect unit.

- RTIN J. KERMER. 

